RubyKaigi 2026
Overview
One of the world's largest international conferences dedicated to the Ruby programming language. Featuring Ruby creator Yukihiro Matsumoto (Matz), Ruby core team members, and developers from around the globe, the event offers deeply technical talks on language implementation, performance optimization, and cutting-edge libraries and frameworks. Held annually since 2006, the conference rotates across cities in Japan.
Speakers
- Yukihiro Matsumoto (Matz) - Ruby creator
- Koichi Sasada - Ruby core developer, YARV/MJIT author
- Aaron Patterson (tenderlove) - Ruby/Rails core team
- Evan Phoenix - Puma creator
- Samuel Williams - Async Ruby pioneer
Foundation
- Founded
- 2006
- Founder
- Ruby no Kai (Japan Ruby Group)
First held in June 2006 at the AIST Waterfront Center in Odaiba, Tokyo, as the 'Japanese Ruby Conference' with approximately 251 attendees. As the Ruby community grew globally, the event evolved into a major international conference attracting Ruby developers from around the world.
Transition
- 2006 First Nihon Ruby Kaigi held in Odaiba (251 attendees)
- 2011 A hiatus announced after RubyKaigi 2011
- 2013 Relaunched as RubyKaigi, adopting the English name as official
- 2018 Held in Sendai; the share of overseas attendees grew and the event settled in as an international conference
- 2026 Held in Hakodate across two venues, Hakodate Arena and Hakodate Citizen Hall
Voices
Three invaluable days to catch up on the latest in Ruby. The rotating venues across Japan make it enjoyable as a trip too.
You can hear Matz's keynote in person and even discuss directly with core team members. The warmth of the technical community is truly felt.
Student tickets at 5,000 JPY with lunch included. It's great that the event is accessible to younger generations.
Prepped at a study session beforehand, then dove into the PicoRuby workshop and the parties (from wako's report, in Japanese)
Eight engineers made the trip to Hakodate for cutting-edge Ruby talks and community time (from Nexway engineers' report, in Japanese)
A note, Inc. backend engineer felt how daily Rails work rests on language internals after the deep-dive sessions, and marveled at Rubyists' energy, out late drinking yet full of life the next morning (from taakuuyaa's report, in Japanese)
In the News
Sponsors
Ruby Sponsors
-
Medley, Inc. -
ITANDI, Inc. -
KOMOJU Co., Ltd. -
Gaji-Labo Inc. -
hacomono Inc. -
IVRy Inc. -
mov inc. -
GMO Internet Group -
ANDPAD Inc. -
Shopify Engineering
Platinum Sponsors
-
SmartHR, Inc. -
STORES, Inc. -
Leaner Technologies Inc. -
SmartBank, Inc. -
pixiv Inc. -
ESM, Inc. -
Findy Inc. -
Studist -
Net Protections, Inc. -
OPTiM Corporation -
Link and Motivation Inc. -
giftee Inc. -
mybest,Inc. -
Sentry -
DELTA Co., Ltd. -
kickflow, Inc. -
Linc'well Inc. -
with.inc -
ZOZO, Inc. -
Cookpad Inc. -
Leafea, Inc. -
GA technologies Co., Ltd. -
Timee, Inc. -
TOKIUM Inc. -
Hubble Inc. -
note inc. -
WED, Inc. -
JetBrains s.r.o. -
CrowdWorks, Inc. -
PKSHA Technology Inc. -
stmn,inc.
Gold Sponsors
-
Coincheck, Inc. -
TenshokuDRAFT -
Hello, Inc. -
Treasure Data -
freee K.K. -
GMO Pepabo, Inc. -
Network Applied Communication Laboratory Ltd. -
TimeTree, Inc. -
ENECHANGE Ltd. -
DeNA Co., Ltd. -
Linkers Corporation -
Studyplus, Inc. -
Karrot -
MNTSQ, Ltd. -
MedPeer, Inc. -
SMS Co., Ltd. -
AppBrew, Inc. -
CodeCast inc. -
Repro Inc. -
Money Forward, Inc. -
foodnia.inc -
Kurashiru, Inc. -
i Cubed Systems, Inc. -
MIXI, Inc. -
SocialPLUS Inc. -
SerpApi, LLC -
codeTakt Inc. -
PoppinsSitter Co., Ltd. -
Headius Enterprises -
Photosynth Inc.
Silver Sponsors
-
TwoGate Inc. -
TakeyuWeb Inc. -
FjordBootCamp -
ClearCode Inc. -
A’s Child Inc. -
Hamee Corp. -
fejo.dk ApS -
iCARE Co.,Ltd. -
Shunju LLC -
Everyleaf Corporation -
FUNDINNO Inc. -
PIXTA Inc. -
Tsukulink Inc. -
Agileware Inc. -
stadium, inc. -
B4A, Inc. -
Ezowin Inc. -
esa LLC -
Ruby Development Inc. -
Fusic Co., Ltd. -
Nexway Co.,Ltd. -
LUXIAR CO.,LTD. -
Rentio Inc.
Source: official sponsor list (as of October 9, 2026)
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